Hybrid ultraviolet photodetectors with high photosensitivity based on TiO2 nanorods array and polyfluorene

The highly oriented array composed of rutile TiO2 nanorods is synthesized by the hydrothermal method on the SnO:F (FTO) substrate. The hybrid UV detector is fabricated via spin-coating a thin layer of poly (9,9-dihexylfluorene) (PFH) on the array. The device characteristics, including I-V curves under UV illumination and time response are studied. Obvious UV photoconductive effect is observed in the device and the response is fast to the switching on and off UV light illumination, which can be repeated for at least 50 times. The quick enhancement of the current origins from the large contact area between TiO2 nanorods and PFH and the convenient charge transport in TiO2 nanorods.